Yes, you are right. Well if other want the wiring sequence they have it. :^)
I Always test with a strong magnetic because some very, very expensive and prestige companies sell junk for high prices. I bought some RCA's one that were high end and loved the magnetic. For the TRRS that is non ferrous, I don't know. I will find out but just buying them without knowing for sure will mostly get you magnetic TRRS plugs. They most likely work fine but when going to this length to get great sound why compromise?